The 3D display device is becoming more and more popular in recent years, because it may enable a viewer to observe a stereo image, which is really true to life. However, the viewer can only observe the 3D image, provided by the current 3D display device, by wearing 3D glasses.
The stereo image is achieved with the aid of the 3D glasses, mostly like shutter glasses, which alternately interrupt a left eye image signal and a right eye image signal that are synchronously projected to a screen, so as to observe the stereo image. FIG. 1 is a schematic view showing shutter glasses in the related art. The shutter glasses include a glass substrate 1 and a glass substrate 2 which are arranged opposite, a liquid crystal layer 3 arranged between the glass substrates 1 and 2, and indium tin oxide (ITO) transparent electrode layers 4 and 5 arranged at opposite sides of the liquid crystal layer 3. Then the left eye image signal and the right eye image signal are alternately interrupted by controlling deflection of liquid crystal molecules in the liquid crystal layers 3 of the left and right lenses through the ITO transparent electrode layers 4 and 5, respectively.
Light is absorbed to a certain extent when passing through the ITO transparent electrode layers 4 and 5, and the transmittance is also decreased after the light passes through the liquid crystal layer 3. As a result, the 3D glasses having the above structure are of poor transmittance. Moreover, because the 3D glasses are provided with the liquid crystal layer 3 and the ITO electrode layer, which results in a complex manufacturing process and a high production cost. In addition, the 3D glasses have a relatively complex electric circuit due to problems such as polarity reversal of the liquid crystal molecules.